Trace gluten contamination may play a role in mucosal and clinical recovery in a subgroup of diet-adherent non-responsive celiac disease patients

Gluten-Free Diet: From Development to Assessment of a Check-List Designed for the Prevention of Gluten Cross-Contamination in Food Services

Gluten cross-contamination in gluten-free food may jeopardize treatment of celiac patients. Considering the deficit of appropriate instruments to enable the implementation of safe production practices for gluten-free food, this study aimed to evaluate the application of a check-list elaborated for gluten cross-contamination prevention in food services. The instrument was applied in 60 Brazilian food services. Interobserver reproducibility and internal consistency of the check-list were tested. A score classification was created for establishments according to the food contamination risk assessment. Subsequent to the application and statistical analysis, the original instrument was reduced to a 30-item check-list. In the reproducibility analysis, none of the 30 items showed significant divergence among the evaluators (p > 0.05 in the Cochran Q test). The 30-item version of the check-list presented Kuder–Richardson Formula 20 (KR-20) = 0.771, indicating good internal consistency. The proposed classification score is obtained by adding 1 point for each item with an “adequate” response; therefore, the final score may vary between 0 and 30 points. Establishments with up to 15 points exhibit risk of gluten contamination, while establishments with a score above 16 points exhibit low risk of contamination. The check-list displayed good reproducibility and internal consistency, suggesting that it could be a useful gluten contamination control instrument in food services.

Gluten-free living in China: The characteristics, food choices and difficulties in following a gluten-free diet - An online survey

BACKGROUND

Individuals adhering to a gluten-free diet (GFD) have been scarcely researched within a Chinese population. This present study was conducted to assess the characteristics, food choices, shopping preferences, and emotions and attitudes of individuals following a GFD.

METHODS

Individuals following a GFD were invited to complete an online questionnaire about their demography and geography characteristics, gluten-free food choices, shopping preferences, GFD management and subjective difficulty towards the diet. Distribution of the characteristics was described, and univariate and multivariate logistic regressions performed to explore the relationship between the above-mentioned variables and subjective difficulty in following a GFD.

RESULT

209 individuals following a GFD completed the questionnaire, most of whom were young, single and well-educated females from developed provinces or municipalities in China. Multiple regression showed that age, education level, advice on starting a GFD, duration before discovering a gluten intolerance, food choices and ways of GFD management were significantly associated with the subjective difficulty in following a GFD.

CONCLUSION

Our findings offer a basic characteristics pattern of the population on a GFD in mainland China. Nearly one-third of GFD followers found the diet challenging to be followed. We suggest that sufficient celiac disease and gluten-induced disorder education be conducted among healthcare practitioners. Early diagnosis of gluten-induced disorders and defining an Asian-adapted GFD, as well as an increase in public awareness, may help adherence to a strict GFD in China.

Clonal T cell receptor gene rearrangements in coeliac disease: implications for diagnosing refractory coeliac disease

Aims

Refractory coeliac disease type II (RCDII), a rare complication of coeliac disease (CD) associated with high morbidity, requires identification of a clonal population of phenotypically aberrant intraepithelial lymphocytes (IELs) for diagnosis. However, data regarding the frequency and significance of clonal T cell receptor (TCR) gene rearrangements (TCR-GRs) in small bowel (SB) biopsies of patients without RCDII are limited.

Methods

We analysed results of TCR-GR analyses performed on SB biopsies at our institution over a 3-year period, which were obtained from eight active CD, 172 CD on gluten-free diet (GFD), 33 RCDI, and three RCDII patients and 14 patients without CD. TCR-GR patterns were divided into clonal, polyclonal and prominent clonal peaks (PCPs) and these patterns were correlated with clinical and pathological features.

Results

Clonal TCR-GR products were detected in biopsies from 67% of patients with RCDII, 17% of patients with RCDI and 6% of patients with GFD. PCPs were observed in all disease phases (range 12%–33%). There was no significant difference in the TCR-GR patterns between the non-RCDII disease categories (p=0.39). A higher frequency of surface CD3(−) IELs was noted in cases with clonal TCR-GR, but the PCP pattern did not show associations with any clinical or pathological feature. Persistence of clonal or PCP pattern on repeat biopsy was seen for up to 2 years without evidence of RCDII.

Conclusions

Clonal TCR-GRs are not infrequent in cases lacking features of RCDII, while PCPs are frequent in all disease phases. TCR-GR results should be assessed in conjunction with immunophenotypic, histological and clinical findings for appropriate diagnosis and classification of RCD.

Coeliac disease

Coeliac disease occurs in about 1% of people in most populations. Diagnosis rates are increasing, and this seems to be due to a true rise in incidence rather than increased awareness and detection. Coeliac disease develops in genetically susceptible individuals who, in response to unknown environmental factors, develop an immune response that is subsequently triggered by the ingestion of gluten. The disease has many clinical manifestations, ranging from severe malabsorption to minimally symptomatic or non-symptomatic presentations. Diagnosis requires the presence of duodenal villous atrophy, and most patients have circulating antibodies against tissue transglutaminase; in children, European guidelines allow a diagnosis without a duodenal biopsy provided that strict symptomatic and serological criteria are met. Although a gluten-free diet is an effective treatment in most individuals, a substantial minority develop persistent or recurrent symptoms. Difficulties adhering to a gluten-free diet have led to the development of non-dietary therapies, several of which are undergoing trials in human beings.

The serological diagnosis of coeliac disease - a step forward

The development of highly performing serological tests to identify patients with coeliac disease (CD), allowed large scale screening studies to be carried out and the results transformed our understanding of the prevalence of the condition in the general population. The next logical step was to ask whether CD could be reliably diagnosed by these tests without the need for small intestinal biopsies. This was shown to be the case. Studies from Derby, UK, indicated that about half of adult patients can be diagnosed in this way and similar figures have been provided for children. When considering this approach, it is essential that laboratories only use highly performing test kits that they have validated to measure tissue transglutaminase antibodies because all kits do not function to the same high standard. There remains a place for biopsy when criteria for serological diagnosis are not met, if the diagnosis of CD is strongly suspected but serological tests are negative or in patients not showing the expected responses to gluten free diet or otherwise causing concern, when not only small bowel biopsy will be indicated but also other investigations. Those with refractory CD should not be compromised by this diagnostic strategy. As serological tests become more refined and information accumulates, it is likely that this mode of diagnosis will gather momentum for the benefit of patients and carers. This brief review looks at the evidence for making the diagnosis of CD in some cases by serological tests alone.

Disease activity indices in coeliac disease: systematic review and recommendations for clinical trials

OBJECTIVE

Although several pharmacological agents have emerged as potential adjunctive therapies to a gluten-free diet for coeliac disease, there is currently no widely accepted measure of disease activity used in clinical trials. We conducted a systematic review of coeliac disease activity indices to evaluate their operating properties and potential as outcome measures in registration trials.

DESIGN

MEDLINE, EMBASE and the Cochrane central library were searched from 1966 to 2015 for eligible studies in adult and/or paediatric patients with coeliac disease that included coeliac disease activity markers in their outcome measures. The operating characteristics of histological indices, patient-reported outcomes (PROs) and endoscopic indices were evaluated for content and construct validity, reliability, responsiveness and feasibility using guidelines proposed by the US Food and Drug Administration (FDA).

RESULTS

Of 19 123 citations, 286 studies were eligible, including 24 randomised-controlled trials. Three of five PROs identified met most key evaluative criteria but only the Celiac Disease Symptom Diary (CDSD) and the Celiac Disease Patient-Reported Outcome (CeD PRO) have been approved by the FDA. All histological and endoscopic scores identified lacked content validity. Quantitative morphometric histological analysis had better reliability and responsiveness compared with qualitative scales. Endoscopic indices were infrequently used, and only one index demonstrated responsiveness to effective therapy.

CONCLUSIONS

Current best evidence suggests that the CDSD and the CeD PRO are appropriate for use in the definition of primary end points in coeliac disease registration trials. Morphometric histology should be included as a key secondary or co-primary end point. Further work is needed to optimise end point configuration to inform efficient drug development.

Self-reported dietary adherence, disease-specific symptoms, and quality of life are associated with healthcare provider follow-up in celiac disease

Background

The only treatment for celiac disease (CeD) is a lifelong gluten-free diet (GFD). The restrictive nature of the GFD makes adherence a challenge. As an integral part of CeD management, multiple professional organizations recommend regular follow-up with a healthcare provider (HCP). Many CeD patients also participate in patient advocacy groups (PAGs) for education and support. Previous work found that follow-up of CeD patients is highly variable. Here we investigated the self-reported factors associated with HCP follow-up among individuals diagnosed with CeD who participate in a PAG.

Methods

We conducted a survey of members of Beyond Celiac (a PAG), collecting responses from 1832 U.S. adults ages 19–65 who reported having CeD. The survey queried HCP follow-up related to CeD and included validated instruments for dietary adherence (CDAT), disease-specific symptoms (CSI), and quality of life (CD-QOL).

Results

Overall, 27% of respondents diagnosed with CeD at least five years ago reported that they had not visited an HCP about CeD in the last five years. The most frequent reason for not visiting an HCP was “doing fine on my own” (47.6%). Using multiple logistic regression, we identified significant associations between whether a respondent reported visiting an HCP about CeD in the last five years and the scores for all three validated instruments. In particular, as disease-specific symptoms and quality of life worsened, the probability of having visited an HCP increased. Conversely, as dietary adherence worsened, the probability decreased.

Conclusions

Our results suggest that many individuals with CeD manage their disease without ongoing support from an HCP. Our results thus emphasize the need for greater access to high quality CeD care, and highlight an opportunity for PAGs to bring together patients and HCPs to improve management of CeD.

Electronic supplementary material

The online version of this article (10.1186/s12876-017-0713-7) contains supplementary material, which is available to authorized users.

Indications and Use of the Gluten Contamination Elimination Diet for Patients with Non-Responsive Celiac Disease

For the majority of patients diagnosed with celiac disease, once a gluten-free diet is initiated, symptoms improve within weeks and may completely resolve in months. However, up to 30% of patients may show signs, symptoms or persistent small intestinal damage after one year on a gluten-free diet. These patients require evaluation for other common GI etiologies and assessment of their celiac disease status in order to make a diagnosis and suggest treatment. Here, we propose an approach to evaluating patients with celiac disease with persistent symptoms, persistently elevated serology, and or persistent villous atrophy despite a gluten-free diet. We detail how to diagnose and distinguish between non-responsive and refractory celiac disease. Finally, we introduce the indications for use of the gluten contamination elimination diet and provide information for practitioners to implement the diet when necessary in their practice.

Tests for Serum Transglutaminase and Endomysial Antibodies Do Not Detect Most Patients With Celiac Disease and Persistent Villous Atrophy on Gluten-free Diets: a Meta-analysis

BACKGROUND & AIMS

Tests to measure serum endomysial antibodies (EMA) and antibodies to tissue transglutaminase (tTG) were developed to screen for celiac disease in patients consuming gluten. However, they are commonly used to monitor patients on a gluten-free diet (GFD). We conducted a meta-analysis to assess the sensitivity and specificity of tTG IgA and EMA IgA assays in identifying patients with celiac disease who have persistent villous atrophy despite a GFD.

METHODS

We searched PUBMED, EMBASE, BIOSIS, SCOPUS, clinicaltrials.gov, Science Citation Index, and Cochrane Library databases through November 2016. Inclusion criteria were studies of subjects with biopsy-confirmed celiac disease, follow-up biopsies, and measurement of serum antibodies on a GFD, biopsy performed on subjects regardless of symptoms, or antibody test results. Our analysis excluded subjects with refractory celiac disease, undergoing gluten challenge, or consuming a prescribed oats-containing GFD. Tests were considered to have positive or negative findings based on manufacturer cut-off values. Villous atrophy was defined as a Marsh 3 lesion or villous height:crypt depth ratio below 3.0. We constructed forest plots to determine the sensitivity and specificity of detection for individual studies. For the meta-analysis, a bivariate random effects model was used to jointly model sensitivity and specificity.

RESULTS

Our search identified 5408 unique citations. Following review of abstracts, 442 articles were reviewed in detail. Only 26 studies (6 of tTG assays, 15 of EMA assays, and 5 of tTG and EMA assays) met our inclusion criteria. The most common reason studies were excluded from our analysis was inability to cross-tabulate histologic and serologic findings. The serum assays identified patients with persistent villous atrophy with high levels of specificity: 0.83 for the tTG IgA assay (95% CI, 0.79-0.87) and 0.91 for the EMA IgA assay (95% CI, 0.87-0.94). However, they detected villous atrophy with low levels of sensitivity: 0.50 for the tTG IgA assay (95% CI, 0.41-0.60) and 0.45 for the EMA IgA assay (95% CI, 0.34-0.57). The tests had similar levels of performance in pediatric and adult patients.

CONCLUSIONS

In a meta-analysis of patients with biopsy-confirmed celiac disease undergoing follow-up biopsy on a GFD, we found that tests for serum tTG IgA and EMA IgA levels had low sensitivity (below 50%) in detection of persistent villous atrophy. We need more-accurate non-invasive markers of mucosal damage in children and adults with celiac disease who are following a GFD.

Understanding Celiac Disease From Genetics to the Future Diagnostic Strategies

Celiac disease (CD) is an autoimmune disorder characterized by the permanent inflammation of the small bowel, triggered by the ingestion of gluten. It is associated with a number of symptoms, the most common being gastrointestinal. The prevalence of this illness worldwide is 1%. One of the main problems of CD is its difficulty to be diagnosed due to the various presentations of the disease. Besides, in many cases, CD is asymptomatic. Celiac disease is a multifactorial disease, HLA-DQ2 and HLA-DQ8 haplotypes are predisposition factors. Nowadays, molecular markers are being studied as diagnostic tools. In this review, we explore CD from its basic concept, manifestations, types, current and future methods of diagnosis, and associated disorders. Before addressing the therapeutic approaches, we also provide a brief overview of CD genetics and treatment.

Small intestinal bacterial overgrowth and celiac disease: A systematic review with pooled-data analysis

BACKGROUND

A link between small intestinal bacterial overgrowth (SIBO) and celiac disease (CD) has been hypothesized.

METHODS

Literature search was performed in main medical databases. Methods of analysis/inclusion criteria were based on Preferred Reporting Items for Systematic reviews and Meta-Analyses recommendations. The end-point was to estimate, by a pooled-data analysis, SIBO prevalence in CD. Proportions/percentages and their 95% confidence intervals (CI) were calculated by inverse variance method, whereas odd ratios (OR) and their 95% CI were estimated, where available, based on the Mantel-Haenszel method. Data were entered into the RevMan 5.3 software.

KEY RESULTS

Eleven articles fulfilled considered criteria. The pooled mean prevalence of SIBO in CD was 20% (95% CI of 10%-30%). In comparison to asymptomatic controls, CD was associated to higher risk of SIBO, with an OR of 10.52 (95% CI 2.69-41.21, P=.0007). Jejunal aspirate culture assessed SIBO prevalence of 11% (95% CI 3%-19%) in CD, whereas breath tests detected a higher value (23%, 95% CI 10%-37%). The pooled prevalence of SIBO in CD patients who were symptomatic despite a GFD was 28% (95% CI 10%-47%), higher than in asymptomatic celiac patients (pooled prevalence of 10%, with a 95% CI of 3%-16%), despite not statistically significant (P=.06). When GFD-unresponsive CD was defined only by clinical persistence of symptoms, the prevalence of SIBO was higher than in the case of villous atrophy association (31% vs 16% P=.33).

CONCLUSIONS

The heterogeneity of available studies may not support a relationship SIBO-CD. Nevertheless, SIBO could be more common in CD when symptoms do not improve after GFD.

Content Validation and Semantic Evaluation of a Check-List Elaborated for the Prevention of Gluten Cross-Contamination in Food Services

Conditions associated to the consumption of gluten have emerged as a major health care concern and the treatment consists on a lifelong gluten-free diet. Providing safe food for these individuals includes adapting to safety procedures within the food chain and preventing gluten cross-contamination in gluten-free food. However, a gluten cross-contamination prevention protocol or check-list has not yet been validated. Therefore, the aim of this study was to perform the content validation and semantic evaluation of a check-list elaborated for the prevention of gluten cross-contamination in food services. The preliminary version of the check-list was elaborated based on the Brazilian resolution for food safety Collegiate Board Resolution 216 (RDC 216) and Collegiate Board Resolution 275 (RDC 275), the standard 22000 from the International Organization for Standardization (ISO 22000) and the Canadian Celiac Association Gluten-Free Certification Program documents. Seven experts with experience in the area participated in the check-list validation and semantic evaluation. The criteria used for the approval of the items, as to their importance for the prevention of gluten cross-contamination and clarity of the wording, was the achievement of a minimal of 80% of agreement between the experts (W-values ≥ 0.8). Moreover, items should have a mean ≥4 in the evaluation of importance (Likert scale from 1 to 5) and clarity (Likert scale from 0 to 5) in order to be maintained in the instrument. The final version of the check-list was composed of 84 items, divided into 12 sections. After being redesigned and re-evaluated, the items were considered important and comprehensive by the experts (both with W-values ≥ 0.89). The check-list developed was validated with respect to content and approved in the semantic evaluation.

Gluten contamination in gluten-free bakery products: a risk for coeliac disease patients

Objective

The present study aimed to assess the safety of gluten-free bakery products for consumption by coeliac patients.

Design/setting

In the current exploratory cross-sectional quantitative study, a total of 130 samples were collected from twenty-five bakeries in Brasilia (Brazil). For the quantification of gluten, an ELISA was used. The threshold of 20 ppm gluten was considered as the safe upper limit for gluten-free food, as proposed in the Codex Alimentarius.

Results

The results revealed a total of 21·5 % of contamination among the bakery products sampled. Sixty-four per cent of the bakeries sold at least one contaminated product in our sample.

Conclusions

These findings represent a risk for coeliac patients since the ingestion of gluten traces may be sufficient to adversely impact on their health.

Risk of Cross-Contact for Gluten-Free Pizzas in Shared-Production Restaurants in Relation to Oven Cooking Procedures

To allow celiac patients to have meals out, a growing number of restaurants and pizzas houses that simultaneously provide gluten-free (GF) pizzas and wheat-based (WB) pizzas have recently been opened in Italy. In these restaurants, GF pizzas are prepared with GF raw materials, following procedures that minimize the risk of gluten cross-contact. Here, we evaluate the risk of gluten cross-contact of GF pizzas in relation to the preparation procedures, thus aiming at identifying a safe procedure for cooking GF pizzas. Our results show that, when specific requirements are complied with, the simultaneous cooking of GF and WB pizzas is a procedure as safe as having an oven dedicated to GF pizzas or the alternate cooking of GF and WB pizzas in the same oven.

Persistent Intraepithelial Lymphocytosis in Celiac Patients Adhering to Gluten-Free Diet Is Not Abolished Despite a Gluten Contamination Elimination Diet

The gluten-free diet (GFD) is the only validated treatment for celiac disease (CD), but despite strict adherence, complete mucosal recovery is rarely obtained. The aim of our study was to assess whether complete restitutio ad integrum could be achieved by adopting a restrictive diet (Gluten Contamination Elimination Diet, GCED) or may depend on time of exposure to GFD. Two cohorts of CD patients, with persisting Marsh II/Grade A lesion at duodenal biopsy after 12–18 months of GFD (early control) were identified. Patients in Cohort A were re-biopsied after a three-month GCED (GCED control) and patients in Cohort B were re-biopsied after a minimum of two years on a standard GFD subsequent to early control (late control). Ten patients in Cohort A and 19 in Cohort B completed the study protocol. There was no change in the classification of duodenal biopsies in both cohorts. The number of intraepithelial lymphocytes, TCRγδ+ (T-Cell Receptor gamma delta) T cell and eosinophils significantly decreased at GCED control (Cohort A) and at late control (Cohort B), compared to early control. Duodenal intraepithelial lymphocytosis persisting in CD patients during GFD is not eliminated by a GCED and is independent of the length of GFD. [NCT 02711696]

Is it gluten-free? Relationship between self-reported gluten-free diet adherence and knowledge of gluten content of foods

OBJECTIVE

To assess the relationship between self-reported adherence to a gluten-free diet (GFD) and the ability to determine correctly the appropriateness of particular foods in a GFD.

METHODS

Persons with celiac disease were recruited through clinics and support groups. Participants completed a questionnaire with items related to GFD information sources, gluten content of 17 common foods (food to avoid, food allowed, and food to question), GFD adherence, and demographic characteristics. Diagnosis was self-reported.

RESULTS

The 82 respondents (88% female) had a median of 6 y GFD experience. Most (55%) reported strict adherence, 18% reported intentional gluten consumption and 21% acknowledged rare unintentional gluten consumption. Cookbooks, advocacy groups, and print media were the most commonly used GFD information sources (85-92%). No participant identified correctly the gluten content of all 17 foods; only 30% identified at least 14 foods correctly. The median score on the Gluten-Free Diet Knowledge Scale (GFD-KS) was 11.5 (interquartile ratio, 10-13). One in five incorrect responses put the respondent at risk of consuming gluten. GFD-KS scores did not correlate with self-reported adherence or GFD duration. Patient advocacy group members scored significantly higher on the GFD-KS than non-members (12.3 versus 10.6; P < 0.005).

CONCLUSIONS

Self-report measures which do not account for the possibility of unintentional gluten ingestion overestimate GFD adherence. Individuals who believe they are following a GFD are not readily able to correctly identify foods that are GF, which suggests ongoing gluten consumption may be occurring, even among patients who believe they are "strictly" adherent. The role of patient advocacy groups and education to improve outcomes through improved adherence to a GFD requires further research.

The Gluten-Free Diet in the 3rd Millennium: Rules, Risks and Opportunities

The gluten-free diet has long been considered the standard treatment for celiac disease. However, a significant number of patients continue to experience persistent symptoms despite following a gluten-free diet. Inadvertent gluten ingestion, fermentable carbohydrates, cross-contamination, and social or financial burdens present obstacles to maintaining a gluten-free diet. Proper diet education and follow-up by an expert Registered Dietitian (RD) is essential to ensure adequate nutrition on the gluten-free diet. Patients may experience unintended weight gain or elevated cholesterol levels after initiating the gluten-free diet due to adequate absorption and healing of the intestines. This review deals with the evolving gluten-free diet, optimal recommendations while considering the overall health of patients, and multi-factorial aspects of the permanent lifestyle change.

A 37-year-old woman with refractory coeliac disease type II disease treated by stem cell transplantation

This case study describes the disease course and treatment of a rare disorder, refractory coeliac disease. This disorder is associated with a marked increase in the risk of development of enteropathy-associated T-cell lymphoma. The patient in question developed coeliac symptoms despite strict adherence to a gluten-free diet, having been symptom-free for over 7 years. She presented with marked oedema of the legs and a distended abdomen. Investigations--laboratory, radiological and enteroscopy findings--were consistent with the development of refractory coeliac disease. This case illustrates the background and course of this disease, and the treatment options.

Advances in diagnosis and management of celiac disease

Celiac disease is an autoimmune disorder that is induced by dietary gluten in genetically predisposed individuals. It has a prevalence of approximately 1% in many populations worldwide. New diagnoses have increased substantially, owing to increased awareness, better diagnostic tools, and probable real increases in incidence. The breadth of recognized clinical presentations continues to expand, making the disorder highly relevant to all physicians. Newer diagnostic tools, including serologic tests for antibodies against tissue transglutaminase and deamidated gliadin peptide, greatly facilitate diagnosis. Tests for celiac-permissive HLA-DQ2 and HLA-DQ8 molecules are useful in defined clinical situations. Celiac disease is diagnosed by histopathologic examination of duodenal biopsy specimens. However, according to recent controversial guidelines, a diagnosis can be made without a biopsy in certain circumstances, especially in children. Symptoms, mortality, and risk for malignancy each can be reduced by adherence to a gluten-free diet. This treatment is a challenge, however, because the diet is expensive, socially isolating, and not always effective in controlling symptoms or intestinal damage. Hence, there is increasing interest in developing nondietary therapies.

Living gluten-free: adherence, knowledge, lifestyle adaptations and feelings towards a gluten-free diet

BACKGROUND

A gluten-free diet (GFD) requires tremendous dedication, involving substantive changes to diet and lifestyle that may have a significant impact upon quality of life. The present study aimed io assess dietary adherence, knowledge of a GFD, and the emotional and lifestyle impact of a GFD.

METHODS

Community dwelling adults following a GFD completed a questionnaire with items related to reasons for avoiding gluten, diagnostic testing, GFD adherence, knowledge and sources of information about a GFD, the Work and Social Adjustment Scale, and the effect of a GFD diet on lifestyle, feelings and behaviours.

RESULTS

Strict GFD adherence among the 222 coeliac disease (CD) patients was 56%. Non-CD individuals (n = 38) were more likely to intentionally ingest gluten (odds ratio = 3.7; 95% confidence interval = 1.4-9.4). The adverse impact of a GFD was modest but most pronounced in the social domain. Eating shifted from the public to the domestic sphere and there were feelings of social isolation. Affective responses reflected resilience because acceptance and relief were experienced more commonly than anxiety or anger. Non-CD respondents were less knowledgeable and less likely to consult health professionals. They experienced less anger and depression and greater pleasure in eating than CD respondents.

CONCLUSIONS

The findings obtained in the present suggest there is good potential for positive adaptation to the demands of a GFD; nevertheless, there is a measurable degree of social impairment that merits further study. The GFD may be a viable treatment option for conditions other than CD; however, education strategies regarding the need for diagnostic testing to exclude CD are required.

The gluten-free diet and its current application in coeliac disease and dermatitis herpetiformis

BACKGROUND

A gluten-free diet (GFD) is currently the only available therapy for coeliac disease (CD).

OBJECTIVES

We aim to review the literature on the GFD, the gluten content in naturally gluten-free (GF) and commercially available GF food, standards and legislation concerning the gluten content of foods, and the vitamins and mineral content of a GFD.

METHODS

We carried out a PubMed search for the following terms: Gluten, GFD and food, education, vitamins, minerals, calcium, Codex wheat starch and oats. Relevant papers were reviewed and for each topic a consensus among the authors was obtained.

CONCLUSION

Patients with CD should avoid gluten and maintain a balanced diet to ensure an adequate intake of nutrients, vitamins, fibre and calcium. A GFD improves symptoms in most patients with CD. The practicalities of this however, are difficult, as (i) many processed foods are contaminated with gluten, (ii) staple GF foods are not widely available, and (iii) the GF substitutes are often expensive. Furthermore, (iv) the restrictions of the diet may adversely affect social interactions and quality of life. The inclusion of oats and wheat starch in the diet remains controversial.

Development of drugs for celiac disease: review of endpoints for Phase 2 and 3 trials

Celiac disease is a lifelong disorder for which there is currently only one known, effective treatment: a gluten-free diet. New treatment approaches have recently emerged; several drugs are in Phase 2 trials and results appear promising; however, discussion around regulatory endpoints is in its infancy. We will briefly discuss the drugs that are under development and then shift our attention to potential trial endpoints, such as patient-reported outcomes, histology, serology, gene expression analysis and other tests. We will outline the differing requirements for proof-of-concept Phase 2 trials and Phase 3 registration trials, with a particular emphasis on current thinking in regulatory agencies. We conclude our paper with recommendations and a glossary of regulatory terms, to enable readers who are less familiar with regulatory language to take maximum advantage of this review.

Non-dietary methods in the treatment of celiac disease

This is a selective review of the literature concerning the methods of celiac disease treatment, which can be an alternative to a gluten-free diet. The most advanced studies are devoted to the larazotide acetate (AT-1001, human zonulin inhibitor) and prolyl-endopeptidases degrading toxic gluten peptides (ALV003, AN-PEP). It is estimated that they will be registered within a few years. They will not become an alternative to the gluten-free diet but rather a supplement to it, which will enable patients to ease the nutritional restrictions.

Advances in coeliac disease

PURPOSE OF REVIEW

To summarize the recent advances in coeliac disease.

RECENT FINDINGS

Details of the polygenic nature of coeliac disease with the human leukocyte antigen (HLA) locus as the dominating genetic element have been uncovered. The existence of a large number of non-HLA coeliac disease genes, only partly shared by each individual patient, suggests the genetic heterogeneity of the disease. The critical role for HLA-DQ-restricted CD4 T cells recognizing antigenic gluten peptides is further substantiated. Involvement of CD8 T cells has received new attention. Other components of wheat than gluten, in particular the amylase trypsin inhibitors, may also play a role. The disease is becoming more prevalent. New guidelines state that coeliac disease diagnosis in children can be made on the basis of clinical signs, serology and genetics without the need of biopsy. The clinical entity 'noncoeliac gluten sensitivity' has received much attention, but diagnostic and pathophysiological definitions are still elusive. The risk for mortality and morbidity in coeliac disease is less than previously thought.

SUMMARY

Our understanding of the basic and clinical aspects of coeliac disease increases. Coeliac disease stands out as a major health problem of almost global occurrence. Case finding, distinguishing coeliac disease from other gluten-sensitive conditions, better care and balanced use of resources are the current challenges.

Persistence of elevated deamidated gliadin peptide antibodies on a gluten-free diet indicates nonresponsive coeliac disease

BACKGROUND

Histologically nonresponsive coeliac disease (NRCD) is a potentially serious condition diagnosed during the follow-up of coeliac disease (CD) when patients have persistent villous atrophy despite following a gluten-free diet (GFD).

AIM

As current assessments of recovery are limited to invasive and costly serial duodenal biopsies, we sought to identify antibody biomarkers for CD patients that do not respond to traditional therapy.

METHODS

Bacterial display peptide libraries were screened by flow cytometry to identify epitopes specifically recognised by antibodies from patients with NRCD, but not by antibodies from responsive CD patients. Deamidated gliadin was confirmed to be the antigen mimicked by library peptides using ELISA with sera from NRCD (n = 15) and responsive CD (n = 45) patients on a strict GFD for at least 1 year.

RESULTS

The dominant consensus epitope sequence identified by unbiased library screening QPxx(A/P)FP(E/D) was highly similar to reported deamidated gliadin peptide (dGP) B-cell epitopes. Measurement of anti-dGP IgG titre by ELISA discriminated between NRCD and responsive CD patients with 87% sensitivity and 89% specificity. Importantly, dGP antibody titre correlated with the severity of mucosal damage indicating that IgG dGP titres may be useful to monitor small intestinal mucosal recovery on a GFD.

CONCLUSIONS

The finding of increased levels of anti-dGP IgG antibodies in CD patients on strict GFDs effectively identifies patients with NRCD. Finally, anti-dGP IgG assays may be useful to monitor mucosal damage and histological improvement in CD patients on a strict GFD.

Refractory coeliac disease in a country with a high prevalence of clinically-diagnosed coeliac disease

BACKGROUND

Refractory coeliac disease (RCD) is thought to be a rare disorder, but the accurate prevalence is unknown.

AIM

We aimed to identify the prevalence of and the risk factors for developing RCD in a Finnish population where the clinical detection rate of coeliac disease is high.

METHODS

The study involved 11 hospital districts in Finland where the number of treated RCD patients (n = 44), clinically diagnosed coeliac disease patients (n = 12 243) and adult inhabitants (n = 1.7 million) was known. Clinical characteristics at diagnosis of coeliac disease between the RCD patients and patients with uncomplicated disease were compared.

RESULTS

The prevalence of RCD was 0.31% among diagnosed coeliac disease patients and 0.002% in the general population. Of the enrolled 44 RCD patients, 68% had type I and 23% type II; in 9% the type was undetermined. Comparing 886 patients with uncomplicated coeliac disease with these 44 patients that developed RCD later in life, the latter were significantly older (median 56 vs 44 years, P < 0.001), more often males (41% vs. 24%, P = 0.012) and seronegative (30% vs. 5%, P < 0.001) at the diagnosis of coeliac disease. Patients with evolving RCD had more severe symptoms at the diagnosis of coeliac disease, including weight loss in 36% (vs. 16%, P = 0.001) and diarrhoea in 54% (vs. 38%, P = 0.050).

CONCLUSIONS

Refractory coeliac disease is very rare in the general population. Patients of male gender, older age, severe symptoms or seronegativity at the diagnosis of coeliac disease are at risk of future refractory coeliac disease and should be followed up carefully.

US perspective on gluten-related diseases

The incidence of allergy and autoimmune disease in the US and other industrialized nations is increasing, and gluten-related disorders are no exception. The US has documented a profound rise in celiac disease that cannot be fully explained by improved serological techniques or better recognition by physicians. Non-celiac gluten sensitivity, a condition only recently recognized by the medical community, has become a commonly diagnosed entity. Proteins, including gluten are increasingly being identified as a source of wheat allergy. Although the gluten free diet represents a safe and effective treatment for these conditions, there is still much to be learned about the development of gluten-related disorders and the apparent increase in incidence within the US. In this article, we present a review of current knowledge on the epidemiology of gluten-related disorders within a global context, with a focus on diagnostic trends and the evaluation of potential risk factors.

IL-17 producing T cells in celiac disease: angels or devils?

Celiac disease (CD) is a very common chronic condition in human beings, affecting approximately one in 100 individuals. It is an autoimmune disease with a defined environmental trigger, the gluten contained in dietary cereals, occurring in genetically susceptible individuals. The disease has a very strong HLA association. More than 90% of CD patients have HLA-DQ2, and almost all of the remaining celiac population possesses HLA-DQ8 molecules. Th17 cells seem to participate in the disease pathogenesis producing and secreting either proinflammatory or anti-inflammatory cytokines.

Diagnostic dilemmas in celiac disease

Celiac disease (CD) is an immune-mediated systemic condition triggered by dietary gluten occurring in genetically susceptible individuals. Our understanding of its numerous and varied clinical presentations has evolved over time, which has contributed to the incidence of CD increasing. In most cases, the diagnosis is readily established and patients promptly improve after commencing a gluten-free diet (GFD). However, in some, the diagnosis is not straightforward and presents a challenge to clinicians. Potential dilemmas include those with positive serology but normal histology, negative serology but abnormal duodenal mucosal histology, failure to respond to a GFD or response to a GFD without evidence of CD. In recent years, development of new assays and modifications to existing diagnostic algorithms for CD has also challenged the traditional role of small-bowel histology as critical in CD diagnosis.